Ceiling construction



March 21, 1933.

c. R. BIRDSEY ET AL CEILING CONSTRUCTION Filed Dec. 12, 1930 2 Sheets-Sheet l March 21, 1933. R B|RD$EY 5- AL 1,902,796

CEILING CONSTRUCTION Filed Dec. 12, 1950 a Sheet-Sheet 2 INVENTOR awn/e1. E5 E1 B/IEDSEK BY HEEBE/PT 14/- E554.

ATTORNE Patented Mar. 21, 1933 UNITED STATES PATENT OFFICE CHARLES R. IBIRDSEY, OF OAK PARK, AND HERBERT W. REEL, OF HINSD'ALE, ILLINOIS,

ASSIGNORS TO UNITED STATES GYPSUM COMPANY, OF CHICAGO, ILLINOIS, A COR- PORATION OF ILLINOIS CEILING CONSTRUCTION Application filed December 12, 1930. Serial No. 501,834.

This invention relates to building constructions and has reference more particularly to the construction of precast ceilings.

In the construction of precast ceilings for buildings, it is desirable to have a construction in which the lower face of the precast tile lies in a single plane, and is without waves or depressions, so that the lower face of the tile may be plastered and present a smooth, even surface. It is also desirable that the precast ceiling tiles be so constructed that they may be installed in the ceiling with a minimum of labor. In certain cases a type of floor construction is used, known as the battleship floor, in which metal plates are welded to the top of structural beams. In such a construction, it becomes necessary to hang the ceiling structure from the'lower flanges of the floor beams. In order to secure ease o'f erection, it is generally desirable to use a grillage system of small parallel structural strips suspended below the main beams of the floor.

An object of this invention, therefore, is to provide a precast ceiling construction, in which the lower faces of the precast tiles present a smooth, even surface for the reception of plaster.

Another object is to provide a ceiling construction which may be erected with a mini-- mum of labor.

A further object of the invention is to provide a ceiling construction suspended from grillage members. and adapted for attachment to the lower flanges of the floor beams; also to improve building constructions in other respects hereinafter specified and claimed.

Reference is to be had to the accompanying drawings forming a part of this specification, in which Fig. 1 is a perspective view of our improved ceiling construction, 7

Fig. 2 is a sectional elevation on a larger scale through the construction,

Fig. 3 is a sectional view through a modified form of the ceiling construction taken on the line 33 of Fig. 4,

Fig. 4 is a sectional elevation through the modified form of ceiling construction shown in Fig. 3,

Fig. 5 is a plan view of the ceiling construction located near a vertical wall,

Fig. 6 is a plan view of the other end of the ceiling construction shown in Fig. 5 adjacent a second vertical wall,

Fig. 7 is a sectional elevation through'the ceiling construction shown in Fig. 5,

Fig. 8 is a sectional elevation through the ceiling construction shown in Fig. 6, taken on the line 8-8 of Fig. 6,

Fig. 9 is a sectional elevation of a modified form of ceiling construction,

Fig. 10 is a sectional elevation showing a modified method of suspending the grillage system, and

Fig. 11 is another sectional elevation showzilrg the suspension system disclosed in Fig.

In the construction of buildings, horizontal floor beams 15 are usually arranged in parallel, spaced relation, being supported at their ends 011 the walls or the vertical structural members of the building. The beams 15 may be of any desired structural shape, such as I beams as shown, having upper flanges 16 and lower flanges 17. While our improved ceiling construction may be used in conjunction with any type of floor construction, we have shown it applied to one form of construction known'as the battleship construction, in which metallic plates 18 rest upon the top flanges 16 of the floor beams, being welded together and to said top flanges by welded seams 19.

The ceiling is formed by a plurality of precast slabs or tiles 20 of gypsum or other cementitious material such as concrete. Interposed between the slabs or tiles 20 and the lower flanges 17 of the floor beams, we prefto the Web 23 of the channels 21 by a. bolt or is shown in Figs. 3 and 4, in which an L- shaped clip has a hook flange 26 resting on the upper surface of the beam flange 17. The lower end of the clip 25 is bent inwardly and then downwardly so as to form a shoulder 26, which engages the lower face of the upper flange 27 of the grillage channels 21. A bolt or rivet 26a then connects a slotted bottom flange 28 of clip 25 to the web 23 of the grillage channel. In this way the shoulder 26 .on the clip 25 engages the channel flange 27 so as to prevent rotation of said clip 25 about the bolt 26a, and thus prevents the hook 26 from being inadvertently disengaged from the flange 17 Another means of attaching the grillage channels 21 to the beams 15.is shown in Figs. 10 and 11. In this form of attachment, a U shaped piece of strap iron 30 is formed so as to engage the edge of the beam flange 17. A heavy wire is bent at its center so as to form a loop 31 engaging the opposite edge of flange 17, then passing transversely of said lower flange and through a pair of openings formed in the clip 30 at the U-bend. The free ends 32 of the wire are then bent downwardly so that said wire engages the clip 30 and confines the flange 17 between said clips and the wire loop 31. The lower ends of the wire 32 are then twisted at 33 below the grillage channel 21 to suspend said grillage channel at a proper height below the beams 15.

If desired, the position of the twist '33 may be changed to replace the upper loop 31. In this modified form of construction the legs 32 of the wire will be previously bent at right angles so as to support the channels 21 at a predetermined distance below the beam flanges 17 The lower ends of the wires may be bent into the form of hooks if desired, so

as to support the channels 21 at a predetermined distance below the beam flanges 17.

Each of the slabs 20 has an outstanding tongue 35 formed on one upper edge thereof, and an outstanding tongue 36 formed on the diagonally opposite, lower edge of said slab. These tongues 35 and 36 are adapted to interengage as shown in Figs. 1 and 2, so that the lower tongue 36 of one tile'supports the upper tongue 35 of the adjoining tile. In order to support the end of the tile adjacent the lower tongue 36. we provide a hook or hanger bar 37 embedded within the tile 20 and extending substantially parallel to the tongue 36. Pockets or recesses 38 are formed in the top surface of the tile to give clearance space for attaching hooks 40 formed on the lower ends of a U-shaped bar 41 which straddles one of the grillage channels 21. The hook bar 37 has a pair of ofl'set sections 42 extending upwardly into the recesses 38 and supported in the hooks 40. The tile 20 is thus supported at one end on the lower flange 36 of the adjoining tile, and at the other endis supported by the hook member 41 extending up over the grillage channels 21. Outstanding tongues 35a are also formed on opposite, diagonal, longitudinal edges of the ties 20, so that said tiles have interlocking tongues around their entire perimeter.

A reinforcing mat 44 is embedded within the slab 20 and has a portion 45 extending upwardly into the tile between the end of the tile and recess 38. The mat 44 then extends downwardly and outwardly to form a loop 46, embedded within the tongue 36. At the opposite end of the tile 20, a loop 47 is' formed on the mat 44 and extends into the tongue 35 to reinforce the same. It will thus be seen that a rugged construction is provided and the tile is properly reinforced to prevent breaking.

It will be seen from an inspection of Figs. 1 and 2, that the portion of the slab 20 outside the hook bar 37 and including the tongue 36, constitutes a cantilever about said hook bar. Stresses set up in said cantilever due to the weight of the adjoining slab, are resisted by the reinforcing mat 44 so that said slab will not break longitudinally ofv said hook bar 37. The recess 38 and hook bar 37 may be spaced away from the tongue 36 a considerable distance so as to increase this cantilever action.

Where our precast ceiling meets the adjoining walls, special provisions are necessary in order to properly support the ceiling and make the tile fit into the space remainin to be filled. Near one of the walls 50, one o the tiles 20 is supported with the upper tongue 35 adjacent the wall. At this point one of the hook rods 37a is loosely supported under the tongue 35 and notches '51 are cut out from the tongue 35 to permit the offset sections 42a to extend upwardly into said notch to receive the supporting hook 40 of the hook bracket 41 which extends over the grillage channel 21.

Near the opposite wall 52, a. space remains which is usually less than the width of the tile. In such a case, (Fig. 9) it is usually preferable to cut out a center section of the tile so that the two remaining pieces 53 and 54 added together will equal the space to be filled by the tile. A piece ofstrap iron 55 having punched holes is then attached to the piece of tile 53 by means of nails 56 driven inwardly through the holes into said piece 53. Holes are also punched at the top of the strap iron 55 for receiving the hooks 40 of the hook bracket 41. It will be noted that the piece 54 contains the outstanding tongue 35 which rests on top of the lower tongue 36 thus supporting the piece in position, it being retained merely by the action of gravity.

In lieu of the arrangement shown in Fig. 9,

the end of the tile having the tongue 35 may be cut OH to leave a tile section 58 (Fig. 7

. face of the tile section 58 to give clearance for the hooks 40,"and a piece of strap iron 60;

is secured to the end of the tile section 58 by means of nails 61, the strap iron 60 being similar in shape to the piece and being adapted to engage the hooks 40 at its upper end. Grout 62 may then be poured into the space above tongue 36 and into the notch 59 so as to maintain the original thickness of the precastceiling at this point and make it uniformly firep-roof'over the entire area of the ceiling.

After erection, there might be some possibility that the hooks 40 might become disengaged from the offset rod section 42 so that the ceiling tile would fall from their position. For the purpose of preyentin this, it is sometimes desirable to place a piece of strap iron 64 into the junction between the upper. tongue 35 and the adjoining tile. 'This piece 64 has a length such' that the upper end'engages the bottom of the grillage channel 21, thus effectively preventing the tile from lifting up to a point where the hooks 40,1nay become disengaged from the rod section 42.

We would state in conclusion that while the illustrated examples constitute a practi cal embodiment of our invention, we do not wish to limit ourselves precisely to these details, since manifestly, the same may be considerably varied without departing from the spirit of the invention as defined in the appended claims.

Having thus described ouriinv'ention, we

claim as new and desire to secure by Letters Patent 1. In a ceiling construction, the combination with a plurality of support bars in spaced parallel relation, of, a plurality of precast ceiling slabs arranged in a plane below said bars, an outstanding tongue formed along each opposite diagonal edge of a slab forming upper and lower tongues, the upper tongue on one edge of each slab being supported solely on the lower tongue of the adjoining slab, said -slab having a recess formed in the upper surface thereof adjacent the lower tongue, a hook bar embedded in said. slab and extending into said recess and hook means engaging said bar in said recess and attached to said support bar.

2. In a ceiling construction, the combination with a plurality of support bars in spaced parallel relation, of a plurality of precast ceiling slabs arranged in a plane below said bars, an outstanding tongue formed along each diagonal edge of the tile forming upper and lower tongues, the upper tongue on one edge of each slab being supported solely on the lower tongue of the adtongue, a hook rod embedded. in said slab and extending into said recess, and a U- shaped attaching member extendlng over a support bar engaging said hook bar within said recess so as to support said slab.

3. In a ceiling construction, the combination with a plurality of support bars in spaced parallel relation, of a plurality of precast ceiling slabs arranged in a plane below said bars, an'outstanding tongue formed along each diagonal edge of the tile forming upper and lower tongues, the upper tongue on one edge of each slab being supported solely on the lower tongue of the adjoining tile, said slab having a recess formed in its upper surface adjacent said lower tongue, a hook bar embedded in said slab and extending into said recess, attaching means engaging said hook bar within said recess and also engaging said support bar, and a .each slab beingsupported on the lower tongue of the adjoining tile, a hook bar embedded in said slab adjacent the lower tongue thereof, said slab having a recess formed in its upper surface spaced apart from the end of said tile into which the hook bar extends, and hook means extending into said recess and engaging said hook bar and said support-bar for supportingsaid slab.

5. In a ceiling construction, the combina-'v ti on with'a plurality of floor beams in spaced parallel relation, said beams having an outstanding lower flange, of a plurality of grillreinforcing mat embedded in said slab and age channels in spaced parallel relation in a plane below said floor beams, each of said channels having an outstanding flange, an attachingclip having a hooked portion engaging the lower flange of said floor beam, an offset section formed on said clip andextending into a position below the upper flange of said channel bar into contact with the web of said channel, attaching means for connecting said offset section, and a shoulder formed on said clip adjacent said offset section adapted to engage the upper flange of said grillage channel to prevent rotation of said attaching clip, and precast ceiling slabs secured to said grillage channels.

6. In a-ceiling construction,-thecombination with a plurality of floor beams in a horizontal plane in spaced parallel relation and adjacent the vertical wall of a buildingi v of a plurality of grillage channels arrange below said beams, a plurality of slabs below said channels each having an outstanding upper tongue formed on an edge thereof adjacent said wall, said tongue having a notch,

formed in the outer edge thereof, a hook bar extending below said tongue and having an offset section extendinginto said notch, and hook means engaging said ofiset section within said notch and also being attached to the supporting channel;

7. In a ceiling construction, the combination with a plurality of support bars in spaced parallel relation, the ends of said bars being positioned adjacent a wall of a building, of a plurality of precast ceiling slabs supported in a plane below said, bars, the V upper'surface of a slab adjacent said wallbeing provided with a recess, a hook bar embedded in said slab and extending into said recess, a hooked member engaging said bar within said recess and being attached to a support bar, an outstanding flange formed on said slab adjacent said reinforcing bar and adjacent said wall, an attaching member nailed to the opposite edge of said slab and extending between said opposite edge and the adjoining slab, and means for connecting said attaching member to a supporttbar'.

8. In a ceiling construction, the combination with a plurality of support bars in spaced parallel relation, of a plurality of precast ceiling slabs arranged in a plane below said bars, an outstanding tongue formed along each opposite, diagonal edge of a slab forming upper and lower tongues, the upper tongue on one edge of each slab being supported on the lower tongue of the adjoining slab, said slab having a recess formed in the upper surface thereof adjacent said lower tongue and spaced apart from said tongue to form a cantilever section, a hook bar embedded in said slab and extending into said recess, hook means engaging said hook bar in said recess andattached to a support bar,

and reinforcing means embedded in saidslab and cantilever section.

CHARLES R. BIRDSEY. HERBERT W. REEL.

neoaree 

